Uvulopalatopharyngoplasty (UPPP) has become a widely accepted method for treating obstructive sleep apnea syndrome (OSAS). The authors studied 52 OSAS patients treated with UPPP and assessed pre- and postoperative parameters including subjective clinical analysis and objective evaluation of computer test. 34(65.38%) OSAS patients felt satisfied of improving snoring sound 3-6 months later following UPPP. 46 patients reported an improvement in their symptoms of daytime somnolence and morning headache. 41 patients underwent follow-up sleep analysis computer (SAC) study; 19 of them (46.34%) had a reduction in AHI more than 50%; meeting our criteria for surgical success. All 41 patients had a significant reduction of total duration of apnea at sleep stage. The study suggests that the effectiveness of UPPP in treating OSAS is limited and subjective clinical symptoms following UPPP do not correlate with the objective finding of SAC; so it is important to stress the significance of follow-up study and necessity to further therapy.